Walls are typically formed in mine tunnels for either controlling the flow of air through the mine or for sealing off abandoned sections of the mine. Mine ventilation walls, also known as brattice walls, are frequently constructed in mines to restrict the flow of air to certain passageways in order to maintain a flow of air to the mine face and all portions of the mine that are actively used by mine personnel. Mine seals or stoppings are typically constructed to seal off mined-out areas or abandoned portions of mines.
Previously, materials used to construct mine seals typically included conventional concrete blocks or prefabricated blocks or panels formed of foam or composites. However, the Sago mine disaster, which involved the failure of a mine seal formed of a dense foam product, proved the futility of constructing mine seals with foam. In that instance, an explosion occurred in a mined-out area that had been sealed only a short time before the disaster. Although mine seals may be constructed of conventional concrete blocks, conventional concrete blocks do not provide the shear strength necessary to withstand high transverse loads or shear forces, such as would be experienced in an explosion.
Accordingly, what is needed is a mine seal or stopping structure that is capable of being rapidly constructed while at the same time is capable of withstanding large transverse loads.